Dissertations / Theses: 'Material texture'

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Wang, Xin. "Intelligent Recognition of Texture and Material Properties of Fabrics." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20349.

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Fabrics are unique materials which consist of various properties affecting their performance and end-uses. A computerized fabric property evaluation and analysis method plays a crucial role not only in textile industry but also in scientific research. An accurate analysis and measurement of fabric property provides a powerful tool for gauging product quality, assuring regulatory compliance and assessing the performance of textile materials. This thesis investigated the solutions for applying computerized methods to evaluate and intelligently interpret the texture and material properties of fabric in an inexpensive and efficient way. Firstly, a method which allows automatic recognition of basic weave pattern and precisely measuring the yarn count is proposed. The yarn crossed-areas are segmented by a spatial domain integral projection approach. Combining fuzzy c-means (FCM) and principal component analysis (PCA) on grey level co-occurrence matrix (GLCM) feature vectors extracted from the segments enables to classify detected segments into two clusters. Based on the analysis on texture orientation features, the yarn crossed-area states are automatically determined. An autocorrelation method is used to find weave repeats and correct detection errors. The method was validated by using computer simulated woven samples and real woven fabric images. The test samples have various yarn counts, appearance, and weave types. All weave patterns of tested fabric samples are successfully recognized and computed yarn counts are consistent to the manual counts. Secondly, we present a methodology for using the high resolution 3D surface data of fabric samples to measure surface roughness in a nondestructive and accurate way. A parameter FDFFT, which is the fractal dimension estimation from 2DFFT of 3D surface scan, is proposed as the indicator of surface roughness. The robustness of FDFFT, which consists of the rotation-invariance and scale-invariance, is validated on a number of computer simulated fractal Brownian images. Secondly, in order to evaluate the usefulness of FDFFT, a novel method of calculating standard roughness parameters from 3D surface scan is introduced. According to the test results, FDFFT has been demonstrated as a fast and reliable parameter for measuring the fabric roughness from 3D surface data. We attempt a neural network model using back propagation algorithm and FDFFT for predicting the standard roughness parameters. The proposed neural network model shows good performance experimentally. Finally, an intelligent approach for the interpretation of fabric objective measurements is proposed using supported vector machine (SVM) techniques. The human expert assessments of fabric samples are used during the training phase in order to adjust the general system into an applicable model. Since the target output of the system is clear, the uncertainty which lies in current subjective fabric evaluation does not affect the performance of proposed model. The support vector machine is one of the best solutions for handling high dimensional data classification. The complexity problem of the fabric property has been optimally dealt with. The generalization ability shown in SVM allows the user to separately implement and design the components. Sufficient cross-validations are performed and demonstrate the performance test of the system.

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Li, Jia. "Ultrasonic Characterization of Polycrystals with Texture and Microtexture: Theory and Experiment." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1418908225.

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Blandford, Peter. "Through-thickness inhomogeneity of steel-sheet texture and its affect on material properties." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59295.

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The work of this thesis centres around two related themes, the first being the characterization of the through-thickness inhomogeneity found in rolled sheet at various stages in its production. The second is involved with attempting to understand how and to what extent the existing inhomogeneity affects the correlations with the anisotropies of some physical or mechanical properties. For this, the inhomogeneity of six steels were measured. Three were specimens removed from the sheet during the early processing of conventional grain-oriented ferrosilicon steel, one sample taken after the first cold rolling stage, another taken after the intermediate anneal, while the last was taken after the following stage, i.e. after the second cold rolling. To contrast the extensive inhomogeneity expected in the ferrosilicon steels, the remaining three steels consisted of two continuous-annealed, interstitial-free, extra-low-carbon steels and one aluminum-killed, batch-annealed, low-carbon steel, all three of which are commercial final product, deep drawing steels.

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Semsari, Parapari Parisa. "Effects of loading mechanisms and texture on ore breakage : A multidimensional study." Licentiate thesis, Luleå tekniska universitet, Mineralteknik och metallurgi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-78068.

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In comminution machines, the product properties (particle size distribution, mineral liberation characteristics) and process consumables (energy for size reduction, wear) are affected by various parameters. On the one hand, understanding and optimizing these parameters can provide an energy efficient process and a specified product. On the other hand, a fundamental understanding of the breakage process can even be used for designing new or improved comminution machines. In this thesis, breakage fundamentals are analyzed and set against the principles of various comminution machines. The study of the breakage fundamentals is crucial for a better understanding of the effect of different comminution environments on ore types and their textures in order to achieve a desired product size and liberation. This work defines three main areas of breakage processes with breakage fundamentals, namely “loading mechanism”, “breakage mechanism” and “breakage mode”. The “loading mechanism” is defined as the physical action that is applied to a particle or several particles in order to introduce mechanical stress. The resulting pattern of the particle failure is named “breakage mechanism”. Finally, the “breakage mode” defines the particle breakage in terms of being random or non‐random. Non‐random breakage depends on the ore texture, which can be categorized as preferential breakage and phase boundary breakage. Promoting the breakage mode to the phase boundary breakage could help to increase the liberation degree. Various studies have assessed the effect of ore texture and operational parameters on mineral liberation. While ore texture is related to the particle inherent characteristics, operational conditions such as loading mechanism are related to the comminution environment. In all these investigations, little attempt has been made to explore the combined effects of loading mechanism and quantitative ore texture features on breakage mode and mineral liberation. In addition, a lack of fundamental understanding of the breakage process and mineral liberation can be seen. Accordingly, a more fundamental study of the causes behind the effects of loading mechanism and texture is required in order to optimize the comminution process in terms of mineral liberation. The objective of this work is, therefore, to investigate the effects of different loading mechanisms on particle breakage and breakage mode. In order to achieve this goal, work has started with using two methods including three‐dimensional deformation and two‐dimensional crack quantification. The former method involved X‐ray computed micro‐tomography (XCT) imaging and Digital Volume Correlation (DVC) measurements which determiners the breakage mode in terms of being random or non-random. Whereas the latter was done using an image processing code in MATLAB to quantify cracks in terms of random and non-random breakage (preferential or phase boundary) from Scanning Electron Microscopy (SEM) images. In addition, XCT 3D imaging was used in order to track the propagated cracks in the third dimension. Moreover, phase boundary breakage in magnetite grains was studied qualitatively based on optical microscopy images in order to identify and characterize the propagated cracks.

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Rice, Stephen Philip. "The spatial variation of bed material texture in coupled basins on the Queen Charlotte Islands." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29788.

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Whether one is interested in the geomorphology, hydrology, or ecology of a river, the nature of the bed sediments is of major importance. Despite a long history of interest our ability to predict local grain size is poor, which is unfortunate given the labour and costs associated with bed material sampling. A preliminary model of sediment texture variation at the drainage basin scale, which makes a fundamental distinction between coupled and uncoupled hillslope-channel units, is presented. It is hypothesised that grain size variations in strongly coupled rivers are unstructured as a result of overbank colluvial inputs and special storage elements. These preclude the development of the systematic downstream structure commonly associated with fluvial sorting and abrasion processes in uncoupled channels. This conjecture is assessed empirically using data collected in two rivers on the Queen Charlotte Islands. It is found that distance alone does not explain changes in grain size, and that local variations are dominated by large organic debris jams. Impermeable jams are associated with upstream fining and downstream coarsening but the effect diminishes as the jams become more permeable, often with age. Jam placement is random, but frequent, and consequently at the drainage basin scale, grain size changes dramatically and unpredictably over very short distances. No deterministic structure is apparent. Further analysis reveals that the observed variations of surface median grain size and Fredle index are best regarded as stochastic phenomena. Sampling criteria are then determined which enable the accurate characterisation of such variation, once a stream has been classified by land use and position relative to hillslopes. Arts, Faculty of Geography, Department of Graduate

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Silber, Marek. "Vytvoření podpůrných výukových prostředků pro kurz Moderní počítačová grafika." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-220541.

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This thesis is divided into two parts, where the first part is focused on an overview and work with 3D software at Czech universities, it includes a comparison of the different programs and description of history of Blender programme which was the one chosen as support for teaching the Modern computer graphics course. The second part of the thesis is more focused on practical matters and describes the basic workings of the programme from the first start up, orientation in the different sections and the settings of the work space for the work itself. The thesis details basic transformation commands of change of location, rotation and change of scale of objects and editing commands like copying, deleting, hiding and duplication of individual objects including their theoretical descriptions. Work with lightings continues after the transformation commands including practical examples of different types of lighting. Work with materials and textures is described in the last two chapters. The goal of this thesis is to describe how to work with the Blender programme and basic work with objects and assigning individual materials and textures for objects and the lighting in a scene for people unfamiliar with the programme.

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Sang, Yucong. "A REPRESENTATION THEOREM FOR MATERIAL TENSORS OF TEXTURED THIN SHEETS WITH WEAK PLANAR ANISOTROPY." UKnowledge, 2018. https://uknowledge.uky.edu/math_etds/57.

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Herein we consider material tensors that pertain to thin sheets or thin films, which we model as two-dimensional objects. We assume that the thin sheet in question carries a crystallographic texture characterized by an orientation distribution function defined on the rotation group SO(3), which is almost transversely-isotropic about the sheet normal so that mechanical and physical properties of the thin sheet have weak planar-anisotropy. We present a procedure by which a special orthonormal basis can be determined in each tensor subspace invariant under the action of the orthogonal group O(2). We call members of such special bases irreducible basis tensors under O(2). For the class of thin sheets in question, we derive a representation formula in which each tensor in any given tensor subspace Z is written as the sum of a transversely-isotropic term and a linear combination of orthonormal irreducible basis tensors in Z, where the coefficients are given explicitly in terms of texture coefficients and undetermined material parameters. In addition to the general representation formula, we present also the specialized form for subspaces of tensor products of second-order symmetric tensors, a type commonly found in mechanics of materials.

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Han, Yi. "Microstructure Representation and Prediction via Convolutional Neural Network-Based Texture Representation and Synthesis, Towards Process Structure Linkage." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/103392.

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Metal additive manufacturing (AM) provides a platform for microstructure optimization via process control, the ability to model the evolution of microstructures from changes in processing condition or even predict the microstructures from given processing condition would greatly reduce the time frame and the cost of the optimization process. In 1, we present a deep learning framework to quantitatively analyze the microstructural variations of metals fabricated by AM under different processing conditions. We also demonstrate the capability of predicting new microstructures from the representation with deep learning and we can explore the physical insights of the implicitly expressed microstructure representations. We validate our framework using samples fabricated by a solid-state AM technology, additive friction stir deposition, which typically results in equiaxed microstructures. In 2, we further improve and generalize the generating framework, a set of metrics is used to quantitatively analyze the effectiveness of the generation by comparing the microstructure characteristics between the generated samples and the originals. We also take advantage of image processing techniques to aid the calculation of metrics that require grain segmentation. Master of Science Different from the traditional manufacturing technique which removes material to form the desired shape, additive manufacturing (AM) adds material together to form the shapes usually layer by layer. AM which is sometimes also referred to as 3-D printing enables the optimization of material property through changing the processing conditions. The microstructure is structures formed by materials on a microscopic scale. Crystals like metal usually form a crystalline structure composed of grains where atoms have the same orientation. Especially for metal AM, changes in the processing condition will usually result in changes in microstructures and material properties. To better optimize for the desired material properties, in 1 we present a microstructure representation method that allows projection of microstructure onto the representation space and prediction from an arbitrary point from the representation space. This representation method allows us to better analyze the changes in microstructure in relation to the changes in processing conditions. In 2, we validate the representation and prediction using EBSD data collected from copper samples manufactured with AM under different processing conditions.

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Vora, Hitesh D. "Integrated Computational and Experimental Approach to Control Physical Texture During Laser Machining of Structural Ceramics." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc407758/.

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The high energy lasers are emerging as an innovative material processing tool to effectively fabricate complex shapes on the hard and brittle structural ceramics, which previously had been near impossible to be machined effectively using various conventional machining techniques. In addition, the in-situ measurement of the thermo-physical properties in the severe laser machining conditions (high temperature, short time duration, and small interaction volume) is an extremely difficult task. As a consequence, it is extremely challenging to investigate the evolution of surface topography through experimental analyses. To address this issue, an integrated experimental and computational (multistep and multiphysics based finite-element modeling) approach was employed to understand the influence of laser processing parameters to effectively control the various thermo-physical effects (recoil pressure, Marangoni convection, and surface tension) during transient physical processes (melting, vaporization) for controlled surface topography (surface finish). The results indicated that the material lost due to evaporation causes an increase in crater depth of machined cavity, whereas liquid expulsion created by the recoil pressure increases the material pileup height around the lip of machined cavity, the major attributes of surface topography (roughness). Also, it was found that the surface roughness increased with increase in laser energy density and pulse rate (from 10 to 50Hz), and with the decrease in distance between two pulses (from 0.6 to 0.1mm) or the increase in lateral and transverse overlap (0, 17, 33, 50, 67, and 83%). The results of the computational model are also validated by experimental observations with reasonably close agreement.

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Kučera, Pavel. "Hodnocení čelního těsnícího provedení povrchu pomocí charakteristik textury povrchu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228286.

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Diploma work dealing with assessments facing the sealing fulfilment surface describes and compares surface topography with the aim of analyzing the most significant characteristic parametrs and factors influencing seal and functional reliability in a decisive way. The most suitable parametrs of sealing which were designated : material ratio Rmr and parametrs Rpk, Rk and Rvk.

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Du, Wenwen. "Material Tensors and Pseudotensors of Weakly-Textured Polycrystals with Orientation Measure Defined on the Orthogonal Group." UKnowledge, 2014. http://uknowledge.uky.edu/math_etds/22.

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Material properties of polycrystalline aggregates should manifest the influence of crystallographic texture as defined by the orientation distribution function (ODF). A representation theorem on material tensors of weakly-textured polycrystals was established by Man and Huang (2012), by which a given material tensor can be expressed as a linear combination of an orthonormal set of irreducible basis tensors, with the components given explicitly in terms of texture coefficients and a number of undetermined material parameters. Man and Huang's theorem is based on the classical assumption in texture analysis that ODFs are defined on the rotation group SO(3), which strictly speaking makes it applicable only to polycrystals with (single) crystal symmetry defined by a proper point group. In the present study we consider ODFs defined on the orthogonal group O(3) and extend the representation theorem of Man and Huang to cover pseudotensors and polycrystals with crystal symmetry defined by any improper point group. This extension is important because many materials, including common metals such as aluminum, copper, iron, have their group of crystal symmetry being an improper point group. We present the restrictions on texture coefficients imposed by crystal symmetry for all the 21 improper point groups and we illustrate the extended representation theorem by its application to elasticity.

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Delorme, Fabian. "Influence de la microstructure et de la texture sur les propriétés supraconductrices de céramiques (RE,Y)Ba2Cu3O7-d texturées. Synthèse et caractérisation." Phd thesis, Université de Caen, 2002. http://tel.archives-ouvertes.fr/tel-00444049.

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Ce travail a été consacré à l'étude de l'influence de différents paramètres microstructuraux sur les propriétés supraconductrices de céramiques d'YBa2Cu3O7-d, texturées par TSMTG, afin d'essayer d'obtenir les meilleures densités de courant critique possibles en vue d'applications. La première partie traite de l'étude d'un paramètre microstructural particulier observé dans les composés REBa2Cu3O7-d : les macles. Une revue des méthodes de caractérisation utilisables a tout d'abord été réalisée, rejetant l'observation par microscopie optique en lumière polarisée et l'enregistrement de « rocking curves ». De nouvelles méthodes ont été proposées pour une analyse qualitative (figures des pôles (200) et (020)) et quantitative (images obtenues à partir des électrons secondaires en microscopie électronique à balayage). Des essais de démaclage de céramiques texturées par traitements thermomécaniques n'ont pas permis d'obtenir d'échantillons démaclés. Une seconde partie traite de l'influence d'ajouts de dopants sur les propriétés supraconductrices. Certains dopants, comme Bi2O3, Gd2O3, Dy2O3, ou Tb(III/IV)O, ont permis d'améliorer nettement les densités de courant critique jusqu'à des valeurs de 95 kA.cm-2 sous champ propre, à 77 K, pour Bi2O3. D'autres dopants se sont avérés diminuer nettement les propriétés supraconductrices comme le calcium. Enfin, un troisième groupe de dopants (par exemple BaF2), ne semble pas changer les microstructures ou les propriétés supraconductrices des céramiques d'YBa2Cu3O7-d. Enfin, la grande fragilité des échantillons de céramiques d'YBa2Cu3O7-d soumis à l'action de l'eau a été mise en évidence dans le cadre d'études sur le stockage de ces matériaux. Un modèle de l'action de l'eau sur les échantillons d'Y123 par un échange Ba2+/« espèce protonée » a été proposé.

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Cimpoi, Mircea. "Recognizing describable attributes of textures and materials in the wild and clutter." Thesis, University of Oxford, 2015. http://ora.ox.ac.uk/objects/uuid:805cb25c-61b4-4c84-9abf-c82ea2b64495.

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Visual textures play an important role in image understanding because theyare a key component of the semantic of many images. Furthermore, texture representations, which pool local image descriptors in an orderless manner, have hada tremendous impact in a wide range of computer vision problems, from texture recognition to object detection. In this thesis we make several contributions to the area of texture understanding. First, we add a new semantic dimension to texture recognition. Instead of focusing on instance or material recognition, we propose a human-interpretable vocabulary of texture attributes, inspired from studies in Cognitive Science, to describe common texture patterns. We also develop a corresponding dataset, the Describable Texture Dataset (DTD), for benchmarking. We show that these texture attributes produce intuitive descriptions of textures. We also show that they can be used to extract a very low dimensional representation of any texture that is very effective in other texture analysis tasks, including improving the state-of-the art in material recognition on the most challenging datasets available today. Second, we look at the problem of recognizing texture attributes and materials in realistic uncontrolled imaging conditions, including when textures appear in clutter. We build on top of the recently proposed Open Surfaces dataset, introduced by the graphics community, by deriving a corresponding benchmarks for material recognition. In addition to material labels, we also augment a subset of Open Surfaces with semantic attributes. Third, we propose a novel texture representation, combining the recent advances in deep-learning with the power of Fisher Vector pooling. We provide thorough evaluation of the new representation, and revisit in general classic texture representations, including bag-of-visual-words, VLAD and the Fisher Vectors, in the context of deep learning. We show that these pooling mechanisms have excellent efficiency and generalisation properties if the convolutional layers of a deep model are used as local features. We obtain in this manner state-of-the-art performance in numerous datasets, both in texture recognition and image understanding in general. We show through our experiments that the proposed representation is an efficient way to apply deep features to image regions, and that it is an effective manner of transferring deep features from one domain to another.

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Erdem, Mehmet Erkut. "Image-based Extraction Of Material Reflectance Properties Of A 3d Object." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1128784/index.pdf.

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In this study, an appearance reconstruction method based on extraction of material re&amp #64258 ectance properties of a three-dimensional (3D) object from its twodimensional (2D) images is explained. One of the main advantages of this system is that the reconstructed object can be rendered in real-time with photorealistic quality in varying illumination conditions. Bidirectional Re&amp #64258 ectance Distribution Functions (BRDFs) are used in representing the re&amp #64258 ectance of the object. The re&amp #64258 ectance of the object is decomposed into di&amp #64256 use and specular components and each component is estimated seperately. While estimating the di&amp #64256 use components, illumination-invariant images of the object are computed from the input images, and a global texture of the object is extracted from these images by using surface particles. The specular re&amp #64258 ectance data are collected from the residual images obtained by taking di&amp #64256 erence between the input images and corresponding illumination-invariant images, and a Lafortune BRDF model is &amp #64257 tted to these data. At the rendering phase, the di&amp #64256 use and specular components are blended into each other to achieve a photorealistic appearance of the reconstructed object.

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SVENSSON, ANNA. "Units." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-17359.

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Breytenbach, Izak Johannes. "A laser-based assessment of road construction aggregate shape and texture properties and their relationship with material shear strength, a pilot study." Thesis, University of Pretoria, 2016. http://hdl.handle.net/2263/53546.

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Experimental research was undertaken to exploit the use of an innovative laser scanning tool and to apply the equipment to the study of (G1) road construction aggregate obtained from crushed rock quarry sources. The aim of the research was to better quantify particle shape and surface texture characteristics and an attempt was made to relate these to the shear strength properties of the materials investigated. By obtaining a better understanding of the effects that particle shape and texture have on the shear strength properties of a material, the overall efficiency of construction aggregate may be improved. Physical material properties and possible effects related to the (geological) origin of the materials were also considered. In order to assess the particle data obtained from scan results, models were derived which could sort individual particles in order, based on their shape and/or surface texture. These models were created by experimental modelling of physical particle properties (i.e. dimensions, volume and surface area) obtained from scan results. A total of 1149 particles scan data were collected. After experimentation, at least two working concept models were proposed using the scan data, one of which was ultimately abandoned as the model was affected by the elongation (i.e. shape) of particles. The second model proved to be better than the first and was further refined to develop a reference system for each particle size to enable comparison of particle textures. After developing the comparative models described above, the aggregate texture value (ATV) was conceived and refined. A system was developed whereby an aggregate texture value was derived for the elongated and regular constituents of an aggregate sample, after separating particle data based on the particles shape. The aggregate texture value weighed in the average model value calculated based on the grading analysis of a particular sample as well as the percentage of elongated particles in a specific size constituent of a sample. The newly developed aggregate texture value was then related to limited tri-axial shear test results to establish whether there is a correlation between the parameter and the shear strength properties of the aggregate. Findings indicate that the models developed and the newly derived aggregate texture value hold significant potential in better quantifying the shear behaviour of aggregates. While this research is based on a limited sample size and data, it is considered a pilot project and the preliminary results justify further, extensive data accumulation and model refinement. Thesis (PhD)--University of Pretoria, 2016. Geology PhD Unrestricted

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Kume, Nelson Yoshiharu. "Texturas plissadas em materiais têxteis: artesanato, técnica e tecnologia." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/100/100133/tde-05072015-181749/.

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O vestuário, tem seu mercado predominantemente norteado por tendências e diferenciais agrega- dos ao produto. Na confecção, estas variáveis são aplicadas ao material têxtil, em sua construção, não tanto nas qualidades internas, mas na aparência. Arranjos sistemáticos na superfície têxtil promovem qualidades táteis e visuais. A textura plissada e sua beleza atemporal é objeto deste estudo. A proposição é percorrer o trabalho histórico para o levantamento das técnicas de produção artesanais e semi-industriais. A partir destas, sistematizar seus conceitos, técnicas e materiais que as reproduzam. Assim, prover aos profissionais e artesãos, conhecimento acessível para o uso em seus serviços e produtos. Artesãos que tem cultuado a arte têxtil a gerações, unem-se à indústria para potencializar suas obras. Artesanalmente, os plissados podem ser reproduzidos a partir de simples materiais de costura domésticos. Os tipos de plissados vão desde os clássicos até os mais elaborados; dos geométricos como os do tipo faca, os orgânicos como os do tipo shibori aos sofisticados como as tesselações. A plissarem semi-industrial, feita com a utilização de fôrmas de papelão permite a reprodução a partir de um padrão. Todos os interessados podem fazer a criação de seus próprios padrões e fôrmas de plissagem com os conceitos de design de superfície e os princípios da dobradura. The clothing has its market predominantly guided by trends and added differentials to the product. In the making, these variables are applied to the textiles in its construction, not so much in inner qualities, but in appearance. Systematic arrangements in the textile surface promote tactile and visual qualities. The pleated texture and its timeless beauty is the subject of this work. The proposition is going through the historical data to survey the handmade and semi-industrial production techniques. From these, systematizing their concepts, techniques and materials to reproduce them. Thus provide professionals and artisans, knowledge accessible for use in your services and products. Artisans who have worshiped the textile art through generations unite in partnership to the industry to enhance their work. Handmade, the pleats can be done with simple household sewing materials. The pleat types range from the classics to the most elaborate; from geometric as knife type and organic as shibori to sophisticated as tessellations. The semi-industrial pleats are made by the use of cardboard molds by which patterns follows chosen standards. Everyone can create an own pattern and pleating molds based on surface design concepts and principles of folding.

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Tiu, Glacialle. "Classification of Drill Core Textures for Process Simulation in Geometallurgy : Aitik Mine, Sweden." Thesis, Luleå tekniska universitet, Mineralteknik och metallurgi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65207.

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This thesis study employs textural classification techniques applied to four different data groups: (1) visible light photography, (2) high-resolution drill core line scan imaging (3) scanning electron microscopy backscattered electron (SEM-BSE) images, and (4) 3D data from X-ray microtomography (μXCT). Eleven textural classes from Aitik ores were identified and characterized. The distinguishing characteristics of each class were determined such as modal mineralogy, sulphide occurrence and Bond work indices (BWI). The textural classes served as a basis for machine learning classification using Random Forest classifier and different feature extraction schemes. Trainable Weka Segmentation was utilized to produce mineral maps for the different image datasets. Quantified textural information for each mineral phase such as modal mineralogy, mineral association index and grain size was extracted from each mineral map. Efficient line local binary patterns provide the best discriminating features for textural classification of mineral texture images in terms of classification accuracy. Gray Level Co-occurrence Matrix (GLCM) statistics from discrete approximation of Meyer wavelets decomposition with basic image statistical features[PK1] (e.g. mean, standard deviation, entropy and histogram derived values) give the best classification result in terms of accuracy and feature extraction time. Differences in the extracted modal mineralogy were observed between the drill core photographs and SEM images which can be attributed to different sample size[PK2] . Comparison of SEM images and 2D μXCT image slice shows minimal difference giving confidence to the segmentation process. However, chalcopyrite is highly underestimated in 2D μXCT image slice, with the volume percentage amounting to only half of the calculated value for the whole 3D sample. This is accounted as stereological error. Textural classification and mineral map production from basic drill core photographs has a huge potential to be used as an inexpensive ore characterization tool. However, it should be noted that this technique requires experienced operators to generate an accurate training data especially for mineral identification and thus, detailed mineralogical studies beforehand is required. Primary Resource Efficiency by Enhanced Prediction (PREP) Center for Advanced Mining and Metallurgy (CAMM)

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guilmeau, emmanuel. "Optimisation des propriétés anisotropes d'échantillons massifs supraconducteurs Bi2223 texturés par frittage-forgeage." Phd thesis, Université de Caen, 2003. http://tel.archives-ouvertes.fr/tel-00009361.

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L'oxyde supraconducteur à haute Tc (Bi,Pb)2Sr2Ca2Cu3O10+x (Bi2223) a été synthétisé par voie sol-gel. Les conditions de calcination et de frittage ont été optimisées afin d'obtenir la phase Bi2223 avec une pureté voisine de 94%. Cette poudre a été mise sous forme de céramiques texturées par frittage-forgeage sous air. Le cycle de forgeage a été optimisé de manière à synthétiser des disques hautement texturés et d'une grande pureté. Des barreaux extraits de ces disques ont été caractérisés en transport. Les meilleures densités de courant critique (Jc) obtenues sont de l'ordre de 10000 A/cm2 (0 T, 77 K) et rejoignent les valeurs maximales présentes à ce jour dans la littérature. Une nouvelle voie de synthèse, consistant à texturer des pastilles composées de la phase Bi2212 et de phases secondaires, a été entreprise. Le contrôle de la taille de particules (⊕<63µm) et des paramètres de frittage-forgeage (845°C/100h) a permis d'atteindre des Jc de l'ordre de 12500 A/cm2. Le broyage planétaire de la poudre sol-gel brûlée s'est avéré précieux pour augmenter sa réactivité et dans le même temps le taux de phase Bi2223 à l'issue du frittage-forgeage. La grande quantité de phase liquide produite pendant la texturation a permis d'améliorer la qualité de la texture via un meilleur alignement des grains et ainsi d'accroître fortement les densités de courant critiques (20000 A/cm2). Par ailleurs, l'empilement de plusieurs disques est possible et rapide, et aboutit à une céramique massive avec des densités de courant critique quasiment identiques à celles obtenues sur un seul disque. L'analyse combinée texture/structure/microstructure traitée via le programme MAUD s'est révélée être d'une grande efficacité pour caractériser nos échantillons. Grâce à la diffraction neutronique, une relation directe entre le taux de phase Bi2223, les paramètres de maille, la taille des cristallites, la densité de distribution maximale et la densité de courant critique a été établie.

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Girard, Antoine. "Nouveaux substrats métalliques à texture biaxiale pour câbles supraconducteurs à haute température critique." Phd thesis, Chambéry, 2006. http://tel.archives-ouvertes.fr/tel-00118093.

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Ce travail rend compte du développement de substrats à texture biaxiale pour les supraconducteurs à hautes températures critiques de seconde génération dit "coated conductor". Le substrat a été obtenu par un procédé de laminage recuit. Les matériaux utilisés sont des alliages industriels Cu55Ni44Mn (Constantan) et le Cu70Ni30. Comparativement au NiW généralement utilisé, ces cupronickels sont non magnétiques à 77 K et permettent donc des applications en courant alternatif ; ils sont en outre moins onéreux. Des essais sur des laminoirs différents, avec ou sans lubrification et en modifiant le taux d'écrouissage ont permis de mettre en évidence des effets de peau et d'optimiser le procédé de déformation. Les températures de recuit ont été choisies à la suite de caractérisations de texture avant et après le recuit ainsi que de mesures in-situ par diffraction de rayons X durs durant la montée en température. Des laminages supérieurs à 98% et des recuits entre 900°C et 950°C en atmosphère protectrice ont permis d'obtenir des rubans ayant une forte texture cubique : désorientations hors du plan (DT) de 5° et dans le plan de 8°. Une partie de la surface est cependant maclée (entre 8% et 10%). Celle-ci entraîne localement de fortes désorientations. L'état de surface a été contrôlé et amélioré par l'utilisation de rouleaux polis miroirs, l'optimisation des conditions de recuit (atmosphère et durée du palier) ainsi que l'ajout d'une étape d'électropolissage. Des essais mécaniques et magnétiques ainsi qu'une étude d'oxydation ont été pratiqués pour vérifier le comportement du ruban dans les conditions d'utilisation comme dans les conditions rencontrées pendant les différents étapes de la réalisation du câble. Le dépôt d'une couche d'oxyde protectrice LZO, sur le substrat a été réalisé avec succès. Les conditions d'un prétraitement sous atmosphère sulfurée, nécessaire à une bonne épitaxie de la couche, ont été déterminées : 1 h à 600°C avec un flux à 0,2 ppm d'H2S. Enfin des essais sur le développement d'un alliage à barrière de diffusion in situ Cu Ni Y permettant de s'affranchir de la première couche tampon ont été menés.

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Mwanga, Abdul-Rahaman. "Development of a geometallurgical testing framework for ore grinding and liberation properties." Doctoral thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-59904.

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Efficient measurement methods for comminution properties are an important prerequisite for testing the variability of an ore deposit within the geometallurgical context. This involves the investigation of effects of mineralogy and mineral texture on the breakage of mineral particles. Breakage properties of mineral particles are crucial for the liberations of minerals and the energy required for that. For process optimization and control purposes, comminution indices are often used to map the variation of processing properties of an entire ore body (e.g. Bond work index). Within the geometallurgical approach this information is then taken up when modelling the process with varying feed properties. The main focus of this thesis work has been to develop a comprehensive geometallurgical testing framework, the Geometallurgical Comminution Test (GCT), which allows the time and cost efficient measurement of grinding indices and their linkage to mineralogical parameters (e.g. modal mineralogy or mineral texture, mineral liberation). In this context a small-scale grindability test has been developed that allows estimating the Bond work index from single pass grinding tests using small amounts of sample material. Verification of the evaluation method and validation was done with different mineral systems. For selected samples the mineral liberation distribution was investigated using automated mineralogy. By transferring the energy-size reduction relation to energy – liberation relation new term liberability has been established. As part of the experimental investigations, mineralogical parameters and mineral texture information were used for predicting breakage and liberation properties. Patterns for describing the breakage phenomena were established for a set of iron oxide ore samples. The determined breakage patterns indicated that the specific rate of mineral breakage slows down when reaching the grain size of mineral particles, thus allowing maximizing mineral liberation significantly without wasting mechanical energy. CAMM

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Mareš, Pavel. "Souvislost vad řezu s řeznými parametry při řezání abrazivním vodním paprskem." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230789.

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The aim of this thesis is to determine the area where there is no random step change in cutting edge roughness. This area is established on the basic of samples created by the abrasive water jet cutting method with variation of technologic parameters.

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PRINCIPATO, LAURA. "Analisi reologiche a supporto dello sviluppo di ingredienti e prodotti innovativi per l'industria alimentare." Doctoral thesis, Università Cattolica del Sacro Cuore, 2022. http://hdl.handle.net/10280/115283.

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La consistenza e l’aroma degli alimenti sono le maggiori discriminanti nell’ambito della qualità/accettabilità di prodotto. Il termine texture include una serie di attributi reologico-strutturali percepibili dall’essere umano attraverso i sensi. La texture è strettamente collegata alla percezione durante la masticazione ma può essere usata anche come strumento per monitorare/controllare la shelf-life del prodotto e per individuare/prevenire eventuali cambiamenti indesiderati nell’alimento. Da qui, stabilire e standardizzare metodi che valutino/descrivano la texture risulta essenziale nello sviluppo di nuovi prodotti. L'obiettivo principale di questo lavoro di tesi è stato lo sviluppo di ingredient/prodotti innovativi con spiccate funzionalità tecnologiche-nutrizionali (riduzione grassi saturi, prodotti a basso contenuto in grassi, prodotti sprayzzabili). Tali soluzioni innovative sono state sviluppate in base alle conoscenze acquisite su prodotti esistenti con lo scopo di mimare o, in alcuni casi, di migliorarne la performance. Per ogni sistema alimentare considerato, protocolli fondati su reologia, texture e, eventualmente, tribologia, sono stati impiegati per caratterizzare il prodotto e le sue funzionalità. Inoltre, i parametri strutturali sono stati correlati con altre tecniche quali l’analisi calorimetrica e l’analisi sensoriale, in modo da definire relazioni tra struttura, stabilità e percezione sensoriale. Food texture and flavor are two major constituents of food quality/acceptability. Food texture is a complex attribute that includes all the rheological/structural features of the product perceptible by means of mechanical, tactile, and where appropriate, visual and auditory receptors of human senses. Texture is fully involved during oral processing, however, it is also exploited along the food chain to assess and monitor quality control on product shelf-life as well as in food formulation to obtain desirable structure thus avoiding undesirable changes in texture. So forth, texture assessing methods are an important, integral tool that should be used in New-Product-Development process in food product design. The main objective of this PhD project was to develop innovative food ingredients/products to comply with several technological e/or nutritional purposes (saturated fat alternatives, low-fat products, sprayable products). The innovative solutions were developed based on the knowledge on existing products to mimic or even improve the performance of the original model. For each system, rheology, texture and, eventually, tribology, were used to develop new methods and relationships to assess food product properties. Among those main instrumental tests, additional characterization techniques such as DSC, QDA and physio-chemical characterization were added to add information.

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DANIEL, Laurent. "Modélisation multi-échelle du comportement magnéto-mécanique des matériaux ferromagnétiques texturés." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2003. http://tel.archives-ouvertes.fr/tel-00004619.

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La thèse porte sur la caractérisation expérimentale et la modélisation des phénomènes de couplages magnéto-mécaniques. Un modèle multi-échelle, considérant successivement l'équilibre d'un domaine magnétique, d'un monocristal (ou grain), et d'un volume élémentaire représentatif est proposé. Ce modèle est appliqué à un alliage de fer-silicium dont on a préalablement caractérisé le comportement magnéto-élastique à l'aide d'un dispositif expérimental spécifique. Les résultats obtenus montrent d'une part la très forte anisotropie du comportement couplé, et, d'autre part l'importance de l'état de contraintes et de la présence de surfaces libres sur le comportement magnéto-élastique. Ces effets sont intégrés au modèle. Quelques applications ou extensions du modèle sont enfin abordées. Elles concernent notamment l'étude de l'effet de la plasticité sur le comportement magnétique ou la détermination d'une contrainte uniaxiale équivalente pour les propriétés magnétiques.

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Christopher, Krauss. "Couches polycristallines orientées d'aragonite biomimétique, synthétisées par voie électrochimique." Phd thesis, Université de Caen, 2009. http://tel.archives-ouvertes.fr/tel-00423427.

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On retrouve CaCO3 dans de nombreux matériaux du Vivant, comme par exemple le corail, les carapaces et les coquilles de différents crustacés et mollusques. La croissance des différentes formes allotropiques de CaCO3 , aragonite, calcite et vatérite, en présence de molécules biologiques, est influencée en terme d'organisation cristalline, de microstructure et d'ordre à grande échelle (texture et ultrastructure). La voie électrochimique a été choisie dans ce travail pour sa vitesse de formation de dépôt ainsi qu'un bon contrôle des paramètres instrumentaux. Nous avons sélectionné l'aragonite dans le dépôt ainsi que sa croissance texturée rappelant celle de la nacre de Haliotis tuberculata tuberculata avec toutefois une orientation cristalline moins prononcée. Une croissance en plaquettes pseudo-hexagonales orientées, présentant un double-maclage et une orientation d'environ 60° les unes par rapport aux autres, rappelle les observations faites sur les nacres de différents mollusques. Une étude par diffraction des rayons X sur des dépôts obtenus en présence de chitosan et de molécules organiques extraites de nacres naturelles montre leur influence sur la texture cristalline, les mailles de l'aragonite et les groupements carbonate. Le décalage de l'atome de carbone par rapport au plan des oxygènes de ce groupement révèle la déformation induite par les molécules durant la croissance cristalline. Cette étude montre que par une approche minérale-organique synthétique, on peut se rapprocher des processus conduisant à la croissance d'organo-cristaux naturels, pour la texture, la distortion de mailles, la structure et le faciès cristallin.

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Vermogen, Alexandre. "Genese des Microstructures et Consequences sur les Proprietes Mecaniques dans les Polymeres Semi-Cristallins Renforces par des Charges Lamellaires." Phd thesis, INSA de Lyon, 2006. http://tel.archives-ouvertes.fr/tel-00173869.

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Ce travail de thèse s'inscrit dans le développement de nouveaux matériaux barrière à matrice semi-cristalline (PE, PA), pour l'emballage alimentaire. A ce titre, l'insertion dans une matrice de polyamide-6 de particules lamellaires de taille nanométrique, du type montmorillonite, permet des améliorations des propriétés barrière, mais aussi des propriétés thermomécaniques, et ce, pour des taux de charge très faibles (<5%). En revanche, dans une matrice polyéthylène, l'ajout d'argile ne conduit pas aux mêmes améliorations des propriétés. Afin de comprendre pourquoi l'ajout de nano-renfort n'induit pas toujours dans les matrices semi-cristallines les effets potentiellement escomptés, ce travail s'articule autour de deux constatations : - la première concerne la caractérisation de la morphologie des nanocomposites à renforts lamellaires : les techniques de Microscopie Electronique à Transmission et Diffraction des Rayons X, utilisées telles qu'elles le sont dans la littérature, ne sont pas adaptées à la caractérisation de ces systèmes. Pour remédier à cela, nous proposons dans une première partie une méthodologie par analyse d'images, de microscopie électronique et optique, pour quantifier l'état de dispersion des feuillets d'argile dans la matrice. Grâce à celle-ci, nous avons montré qu'il était possible d'évaluer des paramètres morphologiques et de dispersion qui peuvent mettre en évidence l'effet de la mise en oeuvre, du taux de charge et de la nature du compatibilisant sur la dispersion et l'exfoliation des particules d'argile. De plus, des expériences complémentaires par SAXS, ESEM et par analyse rhéologique, ont montré que la morphologie par analyse d'images était représentative de la morphologie du nanocomposite dans son ensemble. - la seconde concerne l'analyse des propriétés mécaniques des nanocomposites à matrice semi-cristalline et à renforts lamellaires : celle-ci ne prend pas en compte l'état réel de dispersion, la texture cristalline, l'orientation des particules d'argile ainsi que les interactions renfort-matrice. La deuxième partie de ce travail fait état de l'importance relative de ces différents paramètres sur les propriétés mécaniques. Entre autres, nous avons pu constater que les systèmes les mieux exfoliés n'étaient pas forcément ceux pour lesquels le renforcement était le plus important. Dès lors, nous avons cherché à caractériser la nature du couplage entre les cristallites polymère et les renforts plaquettaires. Deux méthodologies sont proposées. Enfin, une approche qualitative par éléments finis a permis de confirmer le rôle prépondérant des interactions dans le renforcement des nanocomposites lamellaires.

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Nguyen, Thanh Hai. "Modélisation numérique et rhéologie des matériaux à particules déformables." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT273/document.

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Les matériaux à particules hautement déformables sont des formes complexes de matière avec de nombreuses applications en chimie, pharmacie, cosmétique et agro-alimentaire. L’effet conjugué du désordre et des grandes déformations des particules conduit à des propriétés mécaniques nouvelles par rapport aux matériaux à particules indéformables. En particulier, la compressibilité et la résistance au cisaillement sont contrôlées par une combinaison de réarrangements et de changement de forme des particules. Dans ce travail de thèse, nous avons développé une approche numérique originale pour la simulation de ces systèmes. Pour permettre aux particules de se déformer indéfiniment, nous avons modélisé chaque particule par un agrégat de particules primaires sans frottement qui interagissent par une force d’attraction de type Lennard-Jones et une contrainte de non-interpénétration. La dissipation d’énergie par collisions inélastiques entre les particules primaires confère un caractère plastique aux déformations des particules. Nous avons utilisé ce modèle pour étudier les propriétés de compaction et de cisaillement de ces systèmes. Nos résultats ont permis de mettre en évidence le caractère non-linéaire de la compressibilité lorsque la compacité progressivement augmente au-delà de celles des assemblages de particules indéformables. Sous cisaillement, un état critique est atteint avec une dilatance contrôlée par la pression de confinement. Dans cet état, nous avons exploré les distributions des formes des particules, les textures et les distributions des forces pour différentes valeurs de la pression. Nous avons également comparé la compressibilité simulée par l’approche développée avec celle obtenue par la Méthode de Points Matériels (MPM) en utilisant des particules élastiques Soft-particle materials are complex forms of matter that occur in numerous applications in chemical, pharmaceutical, cosmetic and food products. Joint effects of disorder and large particle deformations lead to novel mechanical properties that differ from those of rigid-particle materials. In particular, the compressibility and shear resistance depend on both particle rearrangements and their shape change. In this doctoral work, we developed an original approach for numerical simulation of these systems. To allow the particles to deform without breakage, each particle is modeled as an aggregate of frictionless primary particles interacting via a Lennard-Jones attraction force and impenetrability constraints. Energy dissipation by inelastic collisions between primary particles leads to the plastic nature of particle deformations. This model was used to investigate the compaction and shear behavior of soft-particle systems. We find that the compressibility is strongly nonlinear as the packing fraction increases beyond that of a random close packing of rigid particles. In continuous shearing, a critical state is reached with a dilatancy that depends on the confining pressure. In this state, we investigate the shear resistance, distributions of particle shapes, fabric properties and inter-particle forces as a function of the confining pressure. We also compare our results with those obtained by using the Material Point Method (MPM) with elastic particles

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Raungpaka, Thirada. "conceptual packaging." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/975.

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Packaging and package design is commonly thought of as a tool to attract the consumer to material goods. Packages, however, have other attributes. In Japan, packaging design is very charming because of the delicate selection of materials, images, and interaction. Different kinds of material provide different emotions and appeal to our sense of touch, which can be interpreted in many ways. Packaging lets us directly interact with an object and this experience becomes memorable and intimate. The combination of image and interaction creates another dimension of story telling. My creative project, Conceptual Packaging, is an experiment in using materials and forms to package immaterial concepts and messages such as memories.

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Meslin, Sophie. "Infiltration et croissance des céramiques YBa2Cu3O7-d texturées à structure perforée: relations microstructures et propriétés supraconductrices." Phd thesis, Université de Caen, 2006. http://tel.archives-ouvertes.fr/tel-00126230.

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L'oxyde supraconducteur YBa2Cu3O7Δ (Y123) qui possède une température critique de 92 K a éveillé à sa découverte un grand enthousiasme et est la source de nombreux travaux. Grâce à ses bonnes propriétés supraconductrices à la température de l'azote liquide (77 K) il semble être le plus prometteur pour les applications sous champ magnétique. Pour obtenir des densités de courant critique élevées, il est nécessaire de les densifier et d'induire une orientation cristallographique préférentielle. Ce travail a consisté à élaborer des échantillons plus performants en terme de propriétés supraconductrices. Le procédé conventionnel de texturation induit des fissures et de la porosité dans les échantillons et nécessite l'ajout de dopants pour améliorer ses propriétés. Nous avons étudié un nouveau procédé « infiltration et croissance » ainsi que la mise en forme d'une géométrie originale « à parois minces ». Les caractérisations effectuées sur la microstructure, la texture et les propriétés supraconductrices sont rapportées. L'optimisation du procédé a consisté à comprendre les mécanismes d'infiltration et de croissance, puis à rechercher la configuration et la composition donnant des échantillons les plus performants. Des densités de courants critiques de l'ordre de 68 kA/cm2 en champ propre ont été mesurées à 77 K. L'étude des échantillons perforés a montré que, grâces aux « trous » artificiels, les microstructures sont exempt de porosité, les échantillons se refroidissent plus rapidement et l'oxygénation est plus rapide et homogène comparé aux matériaux non perforés.

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Kenfaui, Driss. "Étude des propriétés mécaniques et thermoélectriques des matériaux Ca3Co4O9 texturés pour la conversion d'énergie." Phd thesis, Université de Caen, 2010. http://tel.archives-ouvertes.fr/tel-00547858.

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L'oxyde thermoélectrique (TE) Ca3Co4O9 se place avantageusement pour les applications de conversion d'énergie en raison de ses bonnes propriétés TE, ses stabilités chimique et thermique à l'air à haute température et l'absence de biotoxicité. Une étude comparative des apports respectifs de procédés de consolidation (frittage conventionnel-CS, pressage à chaud-HP et frittage flash-SPS) a été menée pour déterminer les conditions expérimentales d'obtention de céramiques Ca3Co4O9 aux caractéristiques TE et fiabilité optimisées pour être intégrées dans des dispositifs TE. Par le procédé HP, les conditions optimales (920°C, 30 MPa, 24 h) ont permis d'élaborer des matériaux denses (96 %) et fortement texturés, avec un maxima de pôles {001} de 22 mrd et une croissance notable des grains dans les plans (a,b). Il en découle une faible résistivité ab (5.25 m.cm à 900 K) et donc un facteur de puissance PFab remarquable (595 µW.m-1.K-2). Les caractéristiques mécaniques sont considérablement améliorées en comparaison avec la céramique CS. Des céramiques plus denses (99.6 %) ont été élaborées dans des temps très courts par SPS, mais avec une faible texture. PFab est plus faible que celui obtenu par HP. Les propriétés mécaniques sont toutefois meilleures. D'autre part, des matériaux Ca3Co4O9 multicouches ont été élaborés et les propriétés TE obtenues sont anisotropes. L'anisotropie de la résistivité c/ab vaut 13.5 dans la plage 0-350 K, mais diminue au-delà de 350 K et avoisine 8.8 à 900 K. L'anisotropie PFab/PFc vaut 12 à 900 K. La conductivité thermique abest plus élevée que c. Le facteur de mérite est plus élevé dans les plans (a,b), avec ZTab = 0.16 à 900 K et (ZTab/ ZTc) = 4.6.

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Lucas, Simon. "Le formalisme des micrograins pour le rendu de matériaux poreux." Electronic Thesis or Diss., Bordeaux, 2024. http://www.theses.fr/2024BORD0362.

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Cette thèse porte sur l’impact des structures microscopiques sur l’apparence des matériaux, avec une importance particulière donnée aux matériaux poreux. Nous avons premièrement évalué les modèles d’apparence grâce à des simulations du transport lumineux dans des agrégats de sphères représentant un volume poreux. Nous avons remarqué qu’aucun modèle existant ne correspondait précisément aux simulations et que la majorité des erreurs proviennent des effets surfaciques. Cela nous a incité pour développer un modèle de reflectance bidirectionel (BSDF) spécialisé pour le rendu de couches poreuses, telles que celles que l’on trouve sur les surfaces recouvertes de terres, de poussières, de rouilles. Notre modèle étend la distribution Trowbridge-Reitz (GGX) pour gérer les pores entre des ellipsoïdes opaques, appelés micrograins, et introduit un taux de remplissage dépendant des directions d’observation et d’éclairement afin de mélanger l'apparence de couche poreuse et de la base. En tenant en compte des corrélations entre hauteur et normales ainsi qu’entre l’éclairement et l’observation dans les termes de masquage et d’ombrage, notre modèle produit des effets réalistes difficilement réalisables précédemment comme la rétro-réflexion et les corrélations entre couleurs et hauteurs visibles sur des matériaux réels. Afin d’améliorer l’efficacité des rendus, nous introduisons une méthode d’échantillonnage par importance de la fonction de distribution des normales visibles (vNDF) des micrograins. Au travers de simulations, nous avons validé la précision de notre modèle. Nos travaux décrivent un formalisme complet pour le rendu de couches poreuses et ouvrent de nombreuses perspectives pour des travaux futurs This thesis focuses on the impact of microscopic structures on material appearance, with a particular emphasis on porous materials. We first evaluated existing appearance models by conducting light transport simulations on sphere aggregates representing porous volumes. We found that none of the existing models accurately matched the simulations, with most errors arising from surface effects. This opened the path to the development of a specialized Bidirectional Scattering Distribution Function (BSDF) model for rendering porous layers, such as those found on surfaces covered with dust, rust, or dirt. Our model extends the Trowbridge-Reitz (GGX) distribution to handle pores between elliptical opaque micrograins and introduces a view- and light-dependent filling factor to blend porous and base layers. By adding height-normal and light-view correlations in the masking and shadowing terms, our model produces realistic effects seen in real world materials that were previously hardly obtainable like retro-reflection and height-color correlations. To improve the rendering efficiency of micrograin materials, we introduce an efficient importance sampling routine for visible Normal Distribution Functions (vNDF). Through numerical simulations, we validate the accuracy of our model. Finally, our work provides a comprehensive formalism for rendering porous layers and opens many perspectives of futur work

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Costa, Raquel Aparecida Abrahão [UNESP]. "Materialografia quantitativa de micro estruturas complexas baseada na segmentação por texturas." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/94414.

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Made available in DSpace on 2014-06-11T19:27:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-24Bitstream added on 2014-06-13T19:55:27Z : No. of bitstreams: 1 costa_raa_me_guara.pdf: 2052235 bytes, checksum: a7679d1faabaecae7d1f08931905e615 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) A pesquisa desenvolvida para reconhecimento de padrões estatísticos com base nas informações de textura, ainda possui muitos desafios a serem superados. Um deles é a extração de características a partir de imagens que apresentam pouca variação de contraste. Este trabalho propõe um algoritmo de seleção de características de textura baseado nas característica de Haralick como a correlação e a entropia. A proposta dessa abordagem é tornar possível classificar os dados, linearmente separáveis ou não, em duas ou mais classes levando em conta um pequeno subespaço de características. Foram estudadas técnicas estatísticas para obtenção da textura, para análise e quantificação de colônias A e a fração volumétrica de Widmanstatten, presentes na liga Ti-6Al-4v. A pesquisa culminou no desenvolvimento de um algoritmo e na realização de testes de caracterização baseadas na textura das imagens. No primeiro teste utilizou-se a correlação entre duas áreas, de dimensões diferentes, de uma mesma imagem para identificação de pontos homólogos entre essas imagens onde foi possível a obtenção da fração volumétrica das fases A e B, onde a variação tonal é evidente. Para o segundo teste utilizou-se a correlação entre os mapas de entropia, seguindo o mesmo procedimento anterior para obter os pontos homólogos entre as imagens. A metodologia proposta pode ser aplicada a outros tipos de materiais. A partir dos resultados da fração de área A e a fração de área das colônias A, poderão ser feito ensaios nos quais será possível relacionar as porcentagens citadas com as propriedades mecânicas da liga. The research developed for recognition of statistical patterns based on texture information has still many challenges to be overcome. One of them is characteristics extraction from images which display little contrast variation. This work proposes and algorithm of texture characteristics selection based on Haralick characteristics as correlation and entropy. This iniciation proposal is to make possible to classify data, linearly separable or not, in two or more ranges taking in account a little area of characteristics. It has been studied statistical techniques to obtain texture, for analysis and amount of A colony and Widmanstatten volumeter fraction, present in Ti-6Al-4V alloy. This research has culminated in an algorithm development and in characterization tests accomplishment based on image texture. In the first test there has been used correlation between two areas of different dimension, from the same picture for similar points identification between these images where it has been possible to obtain volumetric fraction of phases A and B where to tonal variation is evident. For the second test it has used correlation between entropy maps, following the previous procedure in order to obtain similar points between the images. The proposed methodology can be applied to other material types. From results of area fraction and A colonies area fraction it can be made tests in which it will be possible to relate the percentages cited with the alloy mechanical properties.

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Kiwanuka, Robert. "Micro-deformation and texture in engineering materials." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:3c924d01-7501-4d59-bb53-07e6584e50c5.

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This DPhil project is set in the context of single crystal elasticity-plasticity finite element modelling. Its core objective was to develop and implement a methodology for predicting the evolution of texture in single and dual-phase material systems. This core objective has been successfully achieved. Modelling texture evolution entails essentially modelling large deformations (as accurately as possible) and taking account of the deformation mechanisms that cause texture to change. The most important deformation mechanisms are slip and twinning. Slip has been modelled in this project and care has been taken to explore conditions where it is the dominant deformation mechanism for the materials studied. Modelling slip demands that one also models dislocations since slip is assumed to occur by the movement of dislocations. In this project a model for geometrically necessary dislocations has been developed and validated against experimental measurements. A texture homogenisation technique which relies on interpretation of EBSD data in order to allocate orientation frequencies based on representative area fractions has been developed. This has been coupled with a polycrystal plasticity RVE framework allowing for arbitrarily sized RVEs and corresponding allocation of crystallographic orientation. This has enabled input of experimentally measured initial textures into the CPFE model allowing for comparison of predictions against measured post-deformation textures, with good agreement obtained. The effect of texture on polycrystal physical properties has also been studied. It has been confirmed that texture indeed has a significant role in determining the average physical properties of a polycrystal. The thesis contributes to the following areas of micro-mechanics materials research: (i) 3D small deformation crystal plasticity finite element (CPFE) modelling, (ii) geometrically necessary dislocation modelling, (iii) 3D large deformation CPFE modelling, (iv) texture homogenisation methods, (v) single and dual phase texture evolution modelling, (vi) prediction of polycrystal physical properties, (vii) systematic calibration of the power law for slip based on experimental data, and (viii) texture analysis software development (pole figures and Kearns factors).

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Dias, Alexandre Henrique de Moura [UNESP]. "Estudo comparativo da textura superficial entre os materiais estéticos indiretos." Universidade Estadual Paulista (UNESP), 2000. http://hdl.handle.net/11449/110741.

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Made available in DSpace on 2014-11-10T11:10:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2000-06-30Bitstream added on 2014-11-10T11:57:20Z : No. of bitstreams: 1 000124943.pdf: 2856695 bytes, checksum: d61150204b12b1d758131e6fb0dbf8e1 (MD5) O propósito deste estudo foi avaliar a rugosidade superficial entre materiais de revestimento estético indiretos (Vita VMK95, Solidex, Artglass, Targis). Para tanto, confeccionaram-se 10 corpos-de-prova nas dimensões de 6mm de comprimento por 6mm de diâmetro de cada material. Uma das superfícies planas recebeu acabamento e polimento, conforme recomendações do fabricante. As amostras concluídas foram submetidas a mensuração, através do rugosímetro Hommel Tester T500. Os valores médios de rugosidade máxima entre os materiais em questão, foram 5,731Jm, 5,151Jm, 6,83 1.1m e 3, 721Jm, respectivamente. A seguir foram submetidos a análise de variância (ANOVA), ao nível de 5%, sendo detectado significância. Concluiu-se que o material Sofidex não apresentou diferença estatisticamente significante entre os grupos, enquanto o Targis apresenta significância estatística em relação ao Artglass e a cerâmica Vita vmk95. The purpose of this study was to evaluate surface rugosity among indirect esthetic materials (Vita VMK 95, Solidex, Artglass, Targis). Ten samples of each material in the cilindric shape with dimension 6 x 6 mm were manufactured. The surface were submitted to finishing and polishing, according to manufacturer's recommendations. The samples were submitted to measuremenst, using the Hommel Tester T500 device. The average values of maxim surface rugosity among the materiais ín question, were 5, 73pm; 5, 15pm; 6, 83 j.Jm e 3, 72 j.Jm, respectively. Sample were also subjectted to variance analysis- ANOVA (5%), had detected significance. Concluded that the material Solidex did not present significant statistical differences among groups, while Targis presented significant statistical differences in relation to the Artglass and the ceramic Vita vmk95.

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Dias, Alexandre Henrique de Moura. "Estudo comparativo da textura superficial entre os materiais estéticos indiretos /." São José dos Campos, 2000. http://hdl.handle.net/11449/110741.

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Orientador: Estevão Tomomitsu Kimpara Banca: Mauro Antonio de Arruda Notelo Banca: Marco Antônio Bottino Resumo: O propósito deste estudo foi avaliar a rugosidade superficial entre materiais de revestimento estético indiretos (Vita VMK95, Solidex, Artglass, Targis). Para tanto, confeccionaram-se 10 corpos-de-prova nas dimensões de 6mm de comprimento por 6mm de diâmetro de cada material. Uma das superfícies planas recebeu acabamento e polimento, conforme recomendações do fabricante. As amostras concluídas foram submetidas a mensuração, através do rugosímetro Hommel Tester T500. Os valores médios de rugosidade máxima entre os materiais em questão, foram 5,731Jm, 5,151Jm, 6,83 1.1m e 3, 721Jm, respectivamente. A seguir foram submetidos a análise de variância (ANOVA), ao nível de 5%, sendo detectado significância. Concluiu-se que o material Sofidex não apresentou diferença estatisticamente significante entre os grupos, enquanto o Targis apresenta significância estatística em relação ao Artglass e a cerâmica Vita vmk95 Abstract: The purpose of this study was to evaluate surface rugosity among indirect esthetic materials (Vita VMK 95, Solidex, Artglass, Targis). Ten samples of each material in the cilindric shape with dimension 6 x 6 mm were manufactured. The surface were submitted to finishing and polishing, according to manufacturer's recommendations. The samples were submitted to measuremenst, using the Hommel Tester T500 device. The average values of maxim surface rugosity among the materiais ín question, were 5, 73pm; 5, 15pm; 6, 83 j.Jm e 3, 72 j.Jm, respectively. Sample were also subjectted to variance analysis- ANOVA (5%), had detected significance. Concluded that the material Solidex did not present significant statistical differences among groups, while Targis presented significant statistical differences in relation to the Artglass and the ceramic Vita vmk95 Mestre

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36

Li, Dongyang. "Texture formation in iron electrodeposits." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29076.

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The texture of electrodeposits has attracted increasing interest, as it is recognized that it is a possible to benefit from the texture and to improve the various properties of electrodeposits or electrolytic coatings. For example, the corrosion resistance of materials is affected by texture. If appropriate textures are introduced in electrodeposited coatings, their corrosion resistance would be enhanced and the coatings will therefore have a longer service time. Texture development during electrodeposition is still poorly understood, and this makes it difficult to control the texture formation during the electrodeposition processes. In order to better understand the texture formation during electrodeposition, extensive theoretical and experimental investigation are undertaken in this thesis. A computer model was proposed to describe texture development. In this model, the microstructure of deposit was represented using a two dimensional triangle lattice. The deposit growth was modelled as previously empty lattice sites are being occupied based on fundamental physical rules. The author proposed that the main driving force for the development of microstructure and texture is the minimization of the system's free energy. This results in texture development, and the minimization of the free energy includes deposit's surface energy and occasionally the magnetic energy. Based on this hypothesis, the texture formation during iron electrodeposition and its variation with the deposition condition were simulated. It was demonstrated that the crystallographic anisotropy of deposit's surface energy plays an important role in the formation of the deposit's fibre texture. The study also indicated that the surface-energy anisotropy could be modified by hydrogen co-deposition and the deposit's texture can be modified by varying the current density, temperature, or pH value of the bath. In addition, the study illustrated that the magnetization energy also plays an important role in texture development during electrodeposition of magnetic materials. When external magnetic fields of sufficient strength are applied during the deposition of magnetic materials, the magnetic fields align grains in such a way that the deposits' fibre textures may transform to non-fibre textures. In order to further justify the minimum-energy texturing mechanism proposed in the model, and to obtain a clear physical picture of the texture formation during electrodeposition, the process of texture development was analyzed using classical thermodynamics. Various experiments were conducted to verify the computer simulation. A positive correlation between the results of the simulation and the experiments were found.

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Thamburaja, Prakash 1974. "Shape memory materials : crystallographic texture and its consequences." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/88855.

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Vempati, Vamsi Krishna. "Texture Evolution In Materials With Layered Crystal Structures." Wright State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=wright1621942851365157.

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39

Forget, Mathilde. "Laminage asymétrique de l'alliage de magnésium AZ31." Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00930193.

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L'alliage de magnésium AZ31 présente une très faible densité. Cette caractéristique en fait un matériau apprécié pour la conception de structures légères. La limitation principale de son utilisation industrielle est sa mauvaise formabilité et ce en raison de la texture cristallographique des tôles qui s'avère être peu adaptée aux procédés de mise en forme tel que l'emboutissage. Cette texture résultant du laminage initial, l'ambition de ce travail est de la modifier en utilisant la technique de laminage asymétrique et de mesurer l'impact de cette voie sur la formabilité de l'alliage. Il a été montré que l'asymétrie, produite par un différentiel de vitesses de rotation des cylindres du laminoir, induit systématiquement de fortes instabilités plastiques sous forme de bandes de cisaillement. Des techniques de cartographie sur microscope électronique en transmission (ACOM) et à balayage (EBSD) ainsi que des analyses de texture par DRX ont été utilisées pour analyser les mécanismes physiques concourant à l'émergence de cette instabilité. Il résulte de cette analyse que l'asymétrie du laminage provoque une forte activité du système de glissement basal que ne compense ni les autres systèmes ni le maclage. Ceci conduit à une localisation marquée de la déformation plastique et à la ruine du matériau.

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40

Derniaux, Eric. "Etude de structures NiCoCrAlY / Al2O3 / TiOx / Pt / AlN déposées par pulvérisation cathodique sur superalliage base Ni pour capteurs de pression haute température." Phd thesis, Caen, 2007. http://tel.archives-ouvertes.fr/tel-00444578.

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Des structures multicouches NiCoCrAlY / Al2O3 / TiOx / Pt / AlN déposées par pulvérisation cathodique sur superalliage base nickel, destinées à la réalisation de capteurs de pression sur pièces de turbomachine, sont étudiées et caractérisées. Les principaux objectifs de l'étude sont de résoudre le problème d'adhérence du film de platine (Pt) sur l'alumine (Al2O3) et d'améliorer la texture cristallographique {0001} des couches de nitrure d'aluminium (AlN) favorable à l'effet piézo-électrique recherché. L'influence d'une couche d'accrochage de TiOx sur l'adhérence du platine et l'effet de la polarisation du substrat sur les propriétés physico-chimiques de l'AlN sont notamment étudiés. L'étude approfondie (diffraction X, MEB, EDS, XPS, tests d'arrachement) des propriétés physico-chimiques des couches est menée. Les résultats mettent en évidence la forte influence du TiOx sur la nature et l'état de surface de l'alumine. La présence d'une couche de TiOx peut améliorer ou dégrader l'adhérence du platine en fonction du type d'alumine élaborée. Un fort effet de la polarisation du substrat sur la texture, la morphologie, la composition chimique de l'AlN et sur les contraintes résiduelles est démontré et expliquée. Les résultats obtenus concernant la qualité de la texture {0001} de l'AlN et la tenue mécanique des structures multicouches (800°C) ont permis la fabrication de transducteurs Pt / AlN / Pt sur substrats plans de superalliage base nickel. La sensibilité à la pression de ces premiers prototypes devra ensuite être évaluée en préalable à l'élaboration de capteurs sur pièces de turbomachine.

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41

Cho, Raymond Young-Jin. "Judging differences between visually textured materials." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28808.pdf.

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Pathak, Ajay Kumar. "Automated defect detection in textured materials." Thesis, Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23295168.

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Zimmermann, Angelo José de Oliveira. "Encruamento, recristalização e textura cristalográfica de zircônio puro e da liga Zircaloy-4." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/3/3133/tde-15102014-163235/.

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Este trabalho consiste em uma pesquisa experimental comparativa entre o zircônio puro e a liga comercial de aplicação nuclear Zircaloy-4, com ênfase nas características de encruamento, recristalização e textura cristalográfica. Foram utilizadas várias técnicas complementares de análise microestrutural tais como microscopia óptica, microscopia eletrônica de varredura com análise química de microrregiões por dispersão de energia de raios X característicos, difração de raios X, calorimetria exploratória diferencial, medidas de dureza e de condutividade elétrica. Para as determinações de macrotextura foi utilizado um goniômetro dedicado de raios X. No estado como recebido, enquanto o zircônio puro apresentava grãos recristalizados com diâmetro médio de aproximadamente 50μm, a liga apresentava granulação alfa em plaquetas grosseiras com diâmetro médio do pré-grão beta de aproximadamente 1,1mm. Experiências de laminação e a determinação de curvas de limite de redução sem a presença de trincas em função da temperatura mostraram que enquanto o zircônio puro apresentou níveis altos de plasticidade na temperatura ambiente, a liga Zircaloy-4 apresentou baixa ductilidade e muitas trincas. As ductilidades dos dois materiais, especialmente da liga Zircaloy-4, aumentaram significativamente a partir de 300°C. A 500°C as ductilidades de ambos são idênticas. Utilizando-se deformações e recozimentos diferenciados foram obtidas tiras de mesma espessura, com grãos equiaxiais e diâmetros médios de grão de aproximadamente 9µm para os dois materiais. Os estudos de recristalização revelaram que, enquanto para o zircônio puro a recuperação contribui significativamente para o amolecimento, no caso da liga Zircaloy-4, o amolecimento ocorre quase que exclusivamente por recristalização. As temperaturas de recristalização do zircônio puro foram mais baixas que as da liga. Os átomos de soluto em solução sólida foram responsáveis pelos dois efeitos concorrentes; aumento da energia armazenada na deformação e aumento da resistência à recristalização. Além da caracterização microestrutural mencionada, foram realizadas determinações de textura cristalográfica para os dois materiais em diferentes condições. Com relação às texturas de laminação do zircônio puro, para uma mesma temperatura, em cerca de 50% de redução a textura de laminado a frio {1 1 2 2} já estava plenamente formada e se alterou muito pouco a partir desta redução, até cerca de 90%. Com o aumento de temperatura de deformação para a mesma redução, a textura de laminado a frio se manteve estável até 300°C. A amostra de Zircaloy-4 preparada para possuir um tamanho de grão de 9 m tinha uma textura próxima de {0 0 0 2} , demonstrando que os tratamentos térmicos e mecânicos utilizados para obtenção dessa amostra foram eficientes na redução da textura de laminado a frio {1 1 2 2} . Recozimentos com duração de uma hora a 550 e 575°C, tanto em zircônio puro como na liga Zircaloy-4, foram suficientes para provocar recristalização estática. A 600°C, uma mudança na orientação cristalográfica foi verificada em Zircaloy-4, tendendo a {0 0 0 2} , enquanto em zircônio puro os planos basais continuam estáveis. O uso de funções de distribuição de orientação cristalográfica (FDOC) auxiliaram na detecção de um segundo grupo orientado, que tende à orientação {1 0 1 1} , além do grupo que reforça as fibras D0 e Rf . A mudança de textura ocorreu durante o crescimento de grão em ambos os materiais. De um modo geral, os resultados mostraram que o zircônio puro tende a ser mais suscetível à recristalização e ao crescimento de grão do que a liga Zircaloy-4. Entretanto, tanto zircônio como a liga são resistentes à modificação de textura, sendo que esta ocorreu principalmente com o crescimento de grão, em temperaturas após a completa recristalização primária. This work shows a comparative experimental research between pure zirconium and the nuclear-grade zirconium alloy Zircaloy-4. This work emphasizes the characteristics of strain hardening, recrystallization, and crystallographic texture. Was used several complementary techniques for microstructural analysis such as optical microscopy, scanning electron microscopy with chemical analysis (EDS), X-ray diffraction, differential scanning calorimetry, indentation hardness and electrical conductivity. For measurements of macrotexture was used a dedicated X-ray goniometer. In the as received state, while pure zirconium showed grains recrystallized with an average diameter of about 50µm, the alloy had rough alpha plates with average diameter of beta pregrain of about 1,1mm. Rolling experiments and determination of reduction limit curves without cracks as a function of temperature showed that while zirconium pure showed high levels of plasticity at room temperature, the alloy zircaloy-4 showed low ductility and many cracks. The ductilities of the two materials, mainly zircaloy-4, significantly increased from 300°C. At 500°C, the ductilities were identical. Using different strains and annealing were obtained strips of equal thickness, with equiaxed grains and grain average diameters of about 9µm for both materials. Recrystallization studies revealed that recovery contributes significantly to softening of pure zirconium. In the case of the alloy zircaloy-4, the softening occurs almost exclusively by recrystallization. The temperature of recrystallization of the pure zirconium were lower than the alloy. The solute atoms in the solid solution were responsible for the two competing effects, the increase of the strain energy stored and the increasing of recrystallization resistance. Crystallographic texture measurements were made for both materials under different conditions. With respect to the rolling textures of pure zirconium, in about 50% reduction of the cold-rolled texture {1 1 2 2} was already fully formed and changed very little from this reduction to about 90%. With the increase of temperature strain to the same reduction, texture cold rolled remained stable up to 300°C. The sample of zircaloy-4 prepared to have a grain size of 9m had a texture close to {0 0 0 2} , demonstrating that the thermal and mechanical treatments used to obtain this sample were effective in reducing texture of cold-rolled {1 1 2 2} . One hour annealings at 550 and 575°C, in pure zirconium and Zircaloy-4, were suffcient to cause static recrystallization. At 600 °C a change in crystallographic orientation was seen in zircaloy-4, tends to {0 0 0 2} , while in pure zirconium the basal planes remains stable. The use of orientation distribution functions (ODF) aided in the detection of a second oriented group, which tends to orientation {1 0 1 1} , besides the group that reinforced D0 and Rf fibers. The change in texture occurred during the grain growth in both materials. In general, the results showed that pure zirconium tends to be more susceptible to recrystallization and grain growth than Zircaloy-4. Nevertheless, Both zinconium and Zircaloy-4 are resistant to texture changes. The texture changes occurred mainly in grain growth, at temperatures after complete recrystallization.

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Keune, Svenja. "On Textile Farming : Seeds as Material for Textile Design." Licentiate thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-13920.

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Presently, designing with living systems such as insects, fungi and bacteria has become an area of extended interest, proposing collaborative processes of designing and manufacturing - as a solution for symbiotic ways of living. On the scale of the interior, modern systems for interior gardening, combining both functional, e.g., food supply, purifying the air, and aesthetic values, experience exceptional popularity, ensuring a complementary perspective on horticultural landscapes indoors. As a result, the spaces where people live and crops grow increasingly intersect and therefore open up for developments that bridge both areas and where aesthetic perspectives become equally important. However, modern indoor gardening systems are shaped by commercial horticultural practices, bringing reservoirs such as buckets, tubs or tanks, mostly built of plastic, into the homes. Textile Farming aims to explore alternative forms of plant organisation by blending seeds and textile structures into a hybrid material for textile interior scenarios. Consequently the materials’ performative capacity becomes part of the textile design process. A foundational part are forms of human management, e.g. activation of the seeds, maintenance of the plants, interaction with the hybrid textile structures within and beyond interiors, that leads to experiences and expressions. By practice based design research and through a series of design examples that explore the transformative potential of seeds in textile structures, alternative forms of plant organisation and methods for the textile design process lead to scenarios that propose alternatives to how we live with and organise plants today. ArcInTexETN

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45

Cho, Jae-Young 1970. "Texture and microstructure in copper damascene interconnects." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85141.

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Copper has been recently used as an interconnecting material since it has high conductivity and good electromigration failure resistance. Recent studies show the close relationship between texture and reliability of Cu damascene interconnects. However, textural and microstructural evolutions of Cu damascene interconnects as function of substrate texture, current density, line width and annealing process are still not well understood. At first, to understand the influence of substrate texture and electroplating conditions on the texture and surface morphology of Cu electrodeposits, three different polycrystalline copper specimens were used as substrates and electrodeposits were plated using different current densities. The mechanism of growth of Cu electrodeposits and the importance of smooth surface morphology were discussed. To analyze the effect of line width and annealing process on textural and microstructural evolution of Cu damascene interconnects, Cu interconnects samples which have a different line width and different annealing process were investigated. According to x-ray diffraction (XRD) and electron backscattered diffraction (EBSD) results, the directional changes of (111) plane orientation with the different line width and annealing were observed. In addition, the analysis of microstructure and grain boundary character distribution (GBCD) of Cu damascene interconnects demonstrated that bamboo-like microstructure was developed in the narrow line and a polygranular structure was developed in the wider line. Also, the fraction of Sigma3 boundaries was changed depending on the line width and annealing process. To analyze a relationship between the stress distribution and textural and microstructural evolution in the samples investigated, stress was calculated using finite element method (FEM), and these results were verified by physical stress simulation of copper in the Chapter 7. Through this investigation, it was found that the inhomogeneity of stress distribution in Cu damascene interconnects is an important factor which is necessary for understanding textural transformation after annealing, and the effects of stress on textural and microstructural evolution of Cu depends on the crystallographic texture and the annealing temperature. A new interpretation of textural and microstructural evolution in Cu damascene interconnects lines after annealing and possible factors responsible for the texture transformation are suggested, and the optimum processing conditions are recommended.

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46

Vopsaroiu, Marian. "Anisotropy and texture studies in magnetic media." Thesis, University of Central Lancashire, 2002. http://clok.uclan.ac.uk/20302/.

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The rapid development of magnetic materials for recording media applications increased the demands for new and more precise experimental investigation techniques. In respect with these demands, this project is focused on experimental analyses of advanced particulate media and magnetic thin film samples. A new extended rotational remanence technique for anisotropy field measurements was developed. The technique is suitable for samples that contain aligned or partially aligned particles and provides both: in-plane anisotropy field distributions and the in-plane anisotropy field. This technique was also extended to out-of-plane anisotropy field measurements. Rotational hysteresis was introduced as an alternative method for anisotropy field measurements. This applies well in the case of samples without texture or samples having very small magnetic moment (i.e. thin films). The two techniques for anisotropy field measurement compare well and the experimental results were interpreted in terms of inter-particles interactions. Two measurement methods for determination of the demagnetizing field acting perpendicular to a sample plane were also developed. The first method is based on the in-plane and out-of-plane anisotropy field determination using an extended rotational remanence technique. The second method can provide the demagnetizing field starting from in-plane and out-of-plane transverse hysteresis loops. Comparison between the results from the two methods showed good agreement. Furthermore, the demagnetizing field values were used to calculate the magnetic coating thickness, so the two methods provide a non-destructive method for magnetic thickness measurements in film samples. The in-plane easy axis distribution (EAD) was experimentally determined using vector VSM techniques. Correlations between in-plane tape texture and magnetic thickness were obtained for a series of advanced MP tapes. A theoretical approach was used in order to relate the orientation ratio to EAD. The out-of-plane EAD was derived from numerical calculations. The out-of-plane distribution also showed a variation with the magnetic thickness. In addition, the microstructure and particle morphology of the advanced MP tapes, as well as the out-of-plane component of magnetization, have been investigated using Mossbauer Spectroscopy. Finally, 3D - EAD maps were produced. All VSM experiments were fully computer controlled and the routines were designed in the LabView environment as part of this project.

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Mengaptche, lowe Jessica. "Sensations et perceptions visuelles et tactiles de matériaux texturés." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEM031/document.

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Les propriétés sensorielles des matériaux constituent un élément important de la valeur perçue. L’enjeu est de mettre en relation 3 espaces de caractérisation des matériaux : un espace physique décrit par des données mesurables par des instruments, un espace psychophysique décrit par des données mesurables par l’appareil perceptif humain, un espace sémantique qui traduit une perception plus globale du matériau. Des méthodes de l’analyse sensorielle sont utilisées pour collecter des données de perception visuelle, tactile et visio-tactile. En parallèle, la sensation tactile est étudiée plus en détail à l’aide d’instruments de tribologie tactile. Les différents jeux d’échantillons sélectionnés permettent d’explorer les 3 espaces de caractérisation. L’analyse des vibrations induites par le contact entre le doigt et des textures artificielles, périodiques et isotropes, montre que la valeur efficace du signal d’accélération ainsi que le coefficient de frottement sont cohérents avec les résultats des tests de perception tactile. En étudiant des archétypes du bois, il apparaît que les échantillons sont différenciés selon deux critères principaux : la rugosité et l’hétérogénéité. Ce dernier faisant référence à la présence ou non de singularités caractéristiques du bois. Par ailleurs, l’analyse des vibrations induites est cohérente avec les résultats des tests de perception tactile. Enfin, l’étude d’un même ensemble de textures présentées sous forme d’un disque de matière et sous forme d’un objet identifié a permis de montrer que, contrairement aux textures artificielles, les textures naturelles ou identifiables sont perçues de manière similaire dans les deux contextes de présentation The sensory properties of material provide leverage of perceived value. The challenge is to relate 3 spaces of material characterization: a physical space describe by measurable data using instruments, a psychophysical space describes by measurable data collected with the human perceptive system, and a semantical space which represent a more global perception of the material. Sensory evaluation methods are used to collect data of visual, tactile and visio-tactile perception. In parallel, the tactile sensation is studied more in detail using tribo-tactile instruments. The different sets of samples allow the exploration of the 3 characterization spaces. The analysis of friction induced vibrations when the finger is scanning periodic and isotropic surfaces reveal that the root mean square value of the acceleration spectra as well as the friction coefficient are coherent with the tactile perception test results. The study of wood archetype texture shows that samples discrimination is based on two main criteria: the roughness and the heterogeneousness, the latter referring to the presence or not of characteristic peculiarities of the wood. Besides, the analysis of friction induced vibrations is also coherent with the results of the tactile perception test. Finally, the study of same set of textures presented in the form of piece of material and in the form of an identified object shows that, contrary to the artificial textures, the natural or familiar textures are perceived in a similar way in both contexts of presentation

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Arshad, Khubaib, and Muhammad Mujahid. "Biodegradation of Textile Materials." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20862.

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In this research work different textile materials were buried in soil and their biodegrading pattern will be studied after different specific period of times. Program: Master Programme in Textile Technology

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Tome, Basheer. "Exoskin : pneumatically augmenting inelastic materials for texture changing interfaces." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101825.

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Thesis: S.M., Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2015. Cataloged from PDF version of thesis. Includes bibliographical references (pages 105-108). Programmable materials have the power to bring to life inert materials in the world around us. Exoskin, provides a way to embed a multitude of static, rigid materials into actuatable, elastic membranes, allowing the new semi-rigid composites to sense, react, and compute. In this thesis, we give an overview of our motivations, design space, and molding architecture that together answer the when, where, and how of Exoskin's use. We then use Exowheel, an automotive steering wheel, as a case study illustrating the concrete benefits and uses of texture change as a multi-modal, bi-directional interface. By incorporating Exoskin, Exowheel is able to transform its surface dynamically to create a customized grip for each individual user, on-the-fly, as well as to adapt the grip during the drive, as the car moves from congested city driving to rougher rural roads. Finally, we introduce the idea of membrane-backed rigid materials as a broader, more versatile platform for introducing texture change and sensing into a variety of other products as well. By deeply embedding soft materials with more-static materials, we can break down the divide between rigid and soft, and animate and inanimate, providing inspiration for Human-Computer Interaction researchers to design more interfaces using physical materials around them, rather than just relying on intangible pixels and their limitations. by Basheer Tome. S.M.

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Lan, Bo. "Texture determination from ultrasound for HCP and cubic materials." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:f0ca1862-154e-4d21-86f1-6bbcba37b555.

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Crystallographic texture in polycrystalline HCP and cubic materials, often developed during thermomechanical deformations, has profound effects on properties at the macroscopic or component level. Given the respective natures of current detection techniques, a non-destructive, three-dimensional bulk texture detection method for these materials has not yet been developed. This thesis aims to achieve this goal through systematic studies on the relationship between ultrasonic wave velocity and texture. The feasibility of such development is firstly reviewed via the combination of computational and experimental studies on exemplary HCP materials. Numerical results obtained via a representative volume element (RVE) methodology reveal that the wave speed varies progressively and significantly with changing texture, and experimental ultrasound studies combined with EBSD characterisation demonstrate distinguished velocity profiles for samples with different textures. Thus the possibility of the development is demonstrated from these combined results. A novel convolution theorem is then presented, which couples the single crystal wave speed (the kernel function) with polycrystal orientation distribution function to give the resultant polycrystal wave speed function. Firstly developed on HCP and then successfully extended to general anisotropic materials, the theorem expresses the three functions as harmonic expansions thus enabling the calculation of any one of them when the other two are known. Hence, the forward problem of determination of polycrystal wave speed is solved for all crystal systems with verifications on varying textures showing near-perfect representation of the sensitivity of wave speed to texture as well as quantitative predictions of polycrystal wave speed. More importantly, the theorem also presents a solution to the long-standing inverse problem for HCP and cubic materials, with proof of principle established where groups of HCP and cubic textures are recovered solely from polycrystal wave velocities through the theorem and the results show good agreements with the original textures. Therefore the theorem opens up the possibility of developing a powerful technique for bulk texture measurement and wave propagation studies in HCP, cubic materials and beyond.

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Dissertations / Theses on the topic 'Material texture'

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